As a mainstream communications technology, Long Term Evolution (LTE for short) may provide a faster data service than a second generation (2G for short) network and a third generation (3G for short) network do. In an LTE data service, data packets of various data services are all transferred on an uplink or downlink data transmission channel established between user equipment (UE for short), an access network, a core network, and a packet data network PDN for short).
To avoid an unnecessary data traffic loss caused by a factor such as a user misoperation or malicious software, a data service switch is disposed for a majority of UEs, and is configured to enable or disable a data service function of the UE. When a user does not need a data service, the user may turn off the data service switch. When a user needs a data service, the user may turn on the data service switch. When the user turns off the data service switch of the UE, the UE usually forbids sending a data packet to a network side by using software and hardware methods, and suspends sending uplink data packets of all data services of the UE. However, a downlink data packet from the network side to the UE may still be sent to the UE on the data transmission channel. This brings an unnecessary data traffic charge for the UE, causing a waste of data traffic of the UE.